On Beijing's northeastern outskirts, a major construction project is under way. It's not an Olympic stadium, apartment blocks, or a massive shopping centre. The site is for something much simpler: water.
In Beijing, as in many large cities, it's not safe to drink the tap water. The rule is either buy bottled water, use purifiers or boil. The real danger here, however, is not just unclean water, but no water at all.